The neural circuitry underlying tic production and suppression is particularly important given the role of voluntary tic control in empirically supported behavioral treatments such as Habit Reversal Training (HRT) for individuals with Chronic Tic Disorders (CTDs), including those with Tourette's Syndrome. Despite a building research base, the etiology and pathophysiology of CTDs remain poorly understood, with existing findings confounded by small sample sizes, developmental effects due to wide age range, medication usage, and uncontrolled psychiatric comorbidity. In response to the NIH R21 call for exploratory or developmental research that have the potential to advance biomedical research, we propose to apply an innovative approach (mobile brain/body imaging [MoBI] to characterizing the neural substrates underlying movement and urge suppression in CTDs. The MoBI approach involves the simultaneous recording and integration of high-definition motion capture video, cortical activity (electroencephalography; EEG) and muscle movements (electromyography; EMG). Use of this leading edge technology will advance our understanding of the neural substrates underlying movement initiation and urge suppression and may allow identification of putative biomarkers for tic generation and suppression. The current study proposes to use the MoBI approach on a sample of 48 children aged 8-12 years old, 24 with CTDs and 24 age-matched typically developing (TD) peers. We will use several paradigms to model the neural substrates underlying voluntary and involuntary movements and test whether CTDs involve quantitative or qualitative deviation in motor network circuitry relative to TD peers. Successful application of the MoBI approach to the problem of discovering and testing brain-based biomarkers for CTD is highly innovative in the context of current research, and also has clear potential for advancing clinical CTD research and practice.